// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// Copyright (C) 2010 Gael Guennebaud <gael.guennebaud@inria.fr>
// Copyright (C) 2010-2016 Konstantinos Margaritis <markos@freevec.org>
//
// This Source Code Form is subject to the terms of the Mozilla
// Public License v. 2.0. If a copy of the MPL was not distributed
// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.

#ifndef EIGEN_COMPLEX32_ALTIVEC_H
#define EIGEN_COMPLEX32_ALTIVEC_H

namespace Eigen {

namespace internal {

    static Packet4ui p4ui_CONJ_XOR = vec_mergeh((Packet4ui)p4i_ZERO, (Packet4ui)p4f_MZERO);  //{ 0x00000000, 0x80000000, 0x00000000, 0x80000000 };
#ifdef __VSX__
#if defined(_BIG_ENDIAN)
    static Packet2ul p2ul_CONJ_XOR1 = (Packet2ul)vec_sld((Packet4ui)p2d_MZERO, (Packet4ui)p2l_ZERO, 8);  //{ 0x8000000000000000, 0x0000000000000000 };
    static Packet2ul p2ul_CONJ_XOR2 = (Packet2ul)vec_sld((Packet4ui)p2l_ZERO, (Packet4ui)p2d_MZERO, 8);  //{ 0x8000000000000000, 0x0000000000000000 };
#else
    static Packet2ul p2ul_CONJ_XOR1 = (Packet2ul)vec_sld((Packet4ui)p2l_ZERO, (Packet4ui)p2d_MZERO, 8);  //{ 0x8000000000000000, 0x0000000000000000 };
    static Packet2ul p2ul_CONJ_XOR2 = (Packet2ul)vec_sld((Packet4ui)p2d_MZERO, (Packet4ui)p2l_ZERO, 8);  //{ 0x8000000000000000, 0x0000000000000000 };
#endif
#endif

    //---------- float ----------
    struct Packet2cf
    {
        EIGEN_STRONG_INLINE explicit Packet2cf() {}
        EIGEN_STRONG_INLINE explicit Packet2cf(const Packet4f& a) : v(a) {}

        EIGEN_STRONG_INLINE Packet2cf pmul(const Packet2cf& a, const Packet2cf& b)
        {
            Packet4f v1, v2;

            // Permute and multiply the real parts of a and b
            v1 = vec_perm(a.v, a.v, p16uc_PSET32_WODD);
            // Get the imaginary parts of a
            v2 = vec_perm(a.v, a.v, p16uc_PSET32_WEVEN);
            // multiply a_re * b
            v1 = vec_madd(v1, b.v, p4f_ZERO);
            // multiply a_im * b and get the conjugate result
            v2 = vec_madd(v2, b.v, p4f_ZERO);
            v2 = reinterpret_cast<Packet4f>(pxor(v2, reinterpret_cast<Packet4f>(p4ui_CONJ_XOR)));
            // permute back to a proper order
            v2 = vec_perm(v2, v2, p16uc_COMPLEX32_REV);

            return Packet2cf(padd<Packet4f>(v1, v2));
        }

        EIGEN_STRONG_INLINE Packet2cf& operator*=(const Packet2cf& b)
        {
            v = pmul(Packet2cf(*this), b).v;
            return *this;
        }
        EIGEN_STRONG_INLINE Packet2cf operator*(const Packet2cf& b) const { return Packet2cf(*this) *= b; }

        EIGEN_STRONG_INLINE Packet2cf& operator+=(const Packet2cf& b)
        {
            v = padd(v, b.v);
            return *this;
        }
        EIGEN_STRONG_INLINE Packet2cf operator+(const Packet2cf& b) const { return Packet2cf(*this) += b; }
        EIGEN_STRONG_INLINE Packet2cf& operator-=(const Packet2cf& b)
        {
            v = psub(v, b.v);
            return *this;
        }
        EIGEN_STRONG_INLINE Packet2cf operator-(const Packet2cf& b) const { return Packet2cf(*this) -= b; }
        EIGEN_STRONG_INLINE Packet2cf operator-(void) const { return Packet2cf(-v); }

        Packet4f v;
    };

    template <> struct packet_traits<std::complex<float>> : default_packet_traits
    {
        typedef Packet2cf type;
        typedef Packet2cf half;
        typedef Packet4f as_real;
        enum
        {
            Vectorizable = 1,
            AlignedOnScalar = 1,
            size = 2,
            HasHalfPacket = 0,

            HasAdd = 1,
            HasSub = 1,
            HasMul = 1,
            HasDiv = 1,
            HasNegate = 1,
            HasAbs = 0,
            HasAbs2 = 0,
            HasMin = 0,
            HasMax = 0,
#ifdef __VSX__
            HasBlend = 1,
#endif
            HasSetLinear = 0
        };
    };

    template <> struct unpacket_traits<Packet2cf>
    {
        typedef std::complex<float> type;
        enum
        {
            size = 2,
            alignment = Aligned16,
            vectorizable = true,
            masked_load_available = false,
            masked_store_available = false
        };
        typedef Packet2cf half;
        typedef Packet4f as_real;
    };

    template <> EIGEN_STRONG_INLINE Packet2cf pset1<Packet2cf>(const std::complex<float>& from)
    {
        Packet2cf res;
        if ((std::ptrdiff_t(&from) % 16) == 0)
            res.v = pload<Packet4f>((const float*)&from);
        else
            res.v = ploadu<Packet4f>((const float*)&from);
        res.v = vec_perm(res.v, res.v, p16uc_PSET64_HI);
        return res;
    }

    template <> EIGEN_STRONG_INLINE Packet2cf pload<Packet2cf>(const std::complex<float>* from) { return Packet2cf(pload<Packet4f>((const float*)from)); }
    template <> EIGEN_STRONG_INLINE Packet2cf ploadu<Packet2cf>(const std::complex<float>* from) { return Packet2cf(ploadu<Packet4f>((const float*)from)); }
    template <> EIGEN_STRONG_INLINE Packet2cf ploaddup<Packet2cf>(const std::complex<float>* from) { return pset1<Packet2cf>(*from); }

    template <> EIGEN_STRONG_INLINE void pstore<std::complex<float>>(std::complex<float>* to, const Packet2cf& from) { pstore((float*)to, from.v); }
    template <> EIGEN_STRONG_INLINE void pstoreu<std::complex<float>>(std::complex<float>* to, const Packet2cf& from) { pstoreu((float*)to, from.v); }

    EIGEN_STRONG_INLINE Packet2cf pload2(const std::complex<float>* from0, const std::complex<float>* from1)
    {
        Packet4f res0, res1;
#ifdef __VSX__
        __asm__("lxsdx %x0,%y1" : "=wa"(res0) : "Z"(*from0));
        __asm__("lxsdx %x0,%y1" : "=wa"(res1) : "Z"(*from1));
#ifdef _BIG_ENDIAN
        __asm__("xxpermdi %x0, %x1, %x2, 0" : "=wa"(res0) : "wa"(res0), "wa"(res1));
#else
        __asm__("xxpermdi %x0, %x2, %x1, 0" : "=wa"(res0) : "wa"(res0), "wa"(res1));
#endif
#else
        *reinterpret_cast<std::complex<float>*>(&res0) = *from0;
        *reinterpret_cast<std::complex<float>*>(&res1) = *from1;
        res0 = vec_perm(res0, res1, p16uc_TRANSPOSE64_HI);
#endif
        return Packet2cf(res0);
    }

    template <> EIGEN_DEVICE_FUNC inline Packet2cf pgather<std::complex<float>, Packet2cf>(const std::complex<float>* from, Index stride)
    {
        EIGEN_ALIGN16 std::complex<float> af[2];
        af[0] = from[0 * stride];
        af[1] = from[1 * stride];
        return pload<Packet2cf>(af);
    }
    template <> EIGEN_DEVICE_FUNC inline void pscatter<std::complex<float>, Packet2cf>(std::complex<float>* to, const Packet2cf& from, Index stride)
    {
        EIGEN_ALIGN16 std::complex<float> af[2];
        pstore<std::complex<float>>((std::complex<float>*)af, from);
        to[0 * stride] = af[0];
        to[1 * stride] = af[1];
    }

    template <> EIGEN_STRONG_INLINE Packet2cf padd<Packet2cf>(const Packet2cf& a, const Packet2cf& b) { return Packet2cf(a.v + b.v); }
    template <> EIGEN_STRONG_INLINE Packet2cf psub<Packet2cf>(const Packet2cf& a, const Packet2cf& b) { return Packet2cf(a.v - b.v); }
    template <> EIGEN_STRONG_INLINE Packet2cf pnegate(const Packet2cf& a) { return Packet2cf(pnegate(a.v)); }
    template <> EIGEN_STRONG_INLINE Packet2cf pconj(const Packet2cf& a) { return Packet2cf(pxor<Packet4f>(a.v, reinterpret_cast<Packet4f>(p4ui_CONJ_XOR))); }

    template <> EIGEN_STRONG_INLINE Packet2cf pand<Packet2cf>(const Packet2cf& a, const Packet2cf& b) { return Packet2cf(pand<Packet4f>(a.v, b.v)); }
    template <> EIGEN_STRONG_INLINE Packet2cf por<Packet2cf>(const Packet2cf& a, const Packet2cf& b) { return Packet2cf(por<Packet4f>(a.v, b.v)); }
    template <> EIGEN_STRONG_INLINE Packet2cf pxor<Packet2cf>(const Packet2cf& a, const Packet2cf& b) { return Packet2cf(pxor<Packet4f>(a.v, b.v)); }
    template <> EIGEN_STRONG_INLINE Packet2cf pandnot<Packet2cf>(const Packet2cf& a, const Packet2cf& b) { return Packet2cf(pandnot<Packet4f>(a.v, b.v)); }

    template <> EIGEN_STRONG_INLINE void prefetch<std::complex<float>>(const std::complex<float>* addr) { EIGEN_PPC_PREFETCH(addr); }

    template <> EIGEN_STRONG_INLINE std::complex<float> pfirst<Packet2cf>(const Packet2cf& a)
    {
        EIGEN_ALIGN16 std::complex<float> res[2];
        pstore((float*)&res, a.v);

        return res[0];
    }

    template <> EIGEN_STRONG_INLINE Packet2cf preverse(const Packet2cf& a)
    {
        Packet4f rev_a;
        rev_a = vec_perm(a.v, a.v, p16uc_COMPLEX32_REV2);
        return Packet2cf(rev_a);
    }

    template <> EIGEN_STRONG_INLINE std::complex<float> predux<Packet2cf>(const Packet2cf& a)
    {
        Packet4f b;
        b = vec_sld(a.v, a.v, 8);
        b = padd<Packet4f>(a.v, b);
        return pfirst<Packet2cf>(Packet2cf(b));
    }

    template <> EIGEN_STRONG_INLINE std::complex<float> predux_mul<Packet2cf>(const Packet2cf& a)
    {
        Packet4f b;
        Packet2cf prod;
        b = vec_sld(a.v, a.v, 8);
        prod = pmul<Packet2cf>(a, Packet2cf(b));

        return pfirst<Packet2cf>(prod);
    }

    EIGEN_MAKE_CONJ_HELPER_CPLX_REAL(Packet2cf, Packet4f)

    template <> EIGEN_STRONG_INLINE Packet2cf pdiv<Packet2cf>(const Packet2cf& a, const Packet2cf& b)
    {
        // TODO optimize it for AltiVec
        Packet2cf res = pmul(a, pconj(b));
        Packet4f s = pmul<Packet4f>(b.v, b.v);
        return Packet2cf(pdiv(res.v, padd<Packet4f>(s, vec_perm(s, s, p16uc_COMPLEX32_REV))));
    }

    template <> EIGEN_STRONG_INLINE Packet2cf pcplxflip<Packet2cf>(const Packet2cf& x) { return Packet2cf(vec_perm(x.v, x.v, p16uc_COMPLEX32_REV)); }

    EIGEN_STRONG_INLINE void ptranspose(PacketBlock<Packet2cf, 2>& kernel)
    {
        Packet4f tmp = vec_perm(kernel.packet[0].v, kernel.packet[1].v, p16uc_TRANSPOSE64_HI);
        kernel.packet[1].v = vec_perm(kernel.packet[0].v, kernel.packet[1].v, p16uc_TRANSPOSE64_LO);
        kernel.packet[0].v = tmp;
    }

    template <> EIGEN_STRONG_INLINE Packet2cf pcmp_eq(const Packet2cf& a, const Packet2cf& b)
    {
        Packet4f eq = reinterpret_cast<Packet4f>(vec_cmpeq(a.v, b.v));
        return Packet2cf(vec_and(eq, vec_perm(eq, eq, p16uc_COMPLEX32_REV)));
    }

#ifdef __VSX__
    template <> EIGEN_STRONG_INLINE Packet2cf pblend(const Selector<2>& ifPacket, const Packet2cf& thenPacket, const Packet2cf& elsePacket)
    {
        Packet2cf result;
        result.v = reinterpret_cast<Packet4f>(pblend<Packet2d>(ifPacket, reinterpret_cast<Packet2d>(thenPacket.v), reinterpret_cast<Packet2d>(elsePacket.v)));
        return result;
    }
#endif

    template <> EIGEN_STRONG_INLINE Packet2cf psqrt<Packet2cf>(const Packet2cf& a) { return psqrt_complex<Packet2cf>(a); }

//---------- double ----------
#ifdef __VSX__
    struct Packet1cd
    {
        EIGEN_STRONG_INLINE Packet1cd() {}
        EIGEN_STRONG_INLINE explicit Packet1cd(const Packet2d& a) : v(a) {}

        EIGEN_STRONG_INLINE Packet1cd pmul(const Packet1cd& a, const Packet1cd& b)
        {
            Packet2d a_re, a_im, v1, v2;

            // Permute and multiply the real parts of a and b
            a_re = vec_perm(a.v, a.v, p16uc_PSET64_HI);
            // Get the imaginary parts of a
            a_im = vec_perm(a.v, a.v, p16uc_PSET64_LO);
            // multiply a_re * b
            v1 = vec_madd(a_re, b.v, p2d_ZERO);
            // multiply a_im * b and get the conjugate result
            v2 = vec_madd(a_im, b.v, p2d_ZERO);
            v2 = reinterpret_cast<Packet2d>(vec_sld(reinterpret_cast<Packet4ui>(v2), reinterpret_cast<Packet4ui>(v2), 8));
            v2 = pxor(v2, reinterpret_cast<Packet2d>(p2ul_CONJ_XOR1));

            return Packet1cd(padd<Packet2d>(v1, v2));
        }

        EIGEN_STRONG_INLINE Packet1cd& operator*=(const Packet1cd& b)
        {
            v = pmul(Packet1cd(*this), b).v;
            return *this;
        }
        EIGEN_STRONG_INLINE Packet1cd operator*(const Packet1cd& b) const { return Packet1cd(*this) *= b; }

        EIGEN_STRONG_INLINE Packet1cd& operator+=(const Packet1cd& b)
        {
            v = padd(v, b.v);
            return *this;
        }
        EIGEN_STRONG_INLINE Packet1cd operator+(const Packet1cd& b) const { return Packet1cd(*this) += b; }
        EIGEN_STRONG_INLINE Packet1cd& operator-=(const Packet1cd& b)
        {
            v = psub(v, b.v);
            return *this;
        }
        EIGEN_STRONG_INLINE Packet1cd operator-(const Packet1cd& b) const { return Packet1cd(*this) -= b; }
        EIGEN_STRONG_INLINE Packet1cd operator-(void) const { return Packet1cd(-v); }

        Packet2d v;
    };

    template <> struct packet_traits<std::complex<double>> : default_packet_traits
    {
        typedef Packet1cd type;
        typedef Packet1cd half;
        typedef Packet2d as_real;
        enum
        {
            Vectorizable = 1,
            AlignedOnScalar = 0,
            size = 1,
            HasHalfPacket = 0,

            HasAdd = 1,
            HasSub = 1,
            HasMul = 1,
            HasDiv = 1,
            HasNegate = 1,
            HasAbs = 0,
            HasAbs2 = 0,
            HasMin = 0,
            HasMax = 0,
            HasSetLinear = 0
        };
    };

    template <> struct unpacket_traits<Packet1cd>
    {
        typedef std::complex<double> type;
        enum
        {
            size = 1,
            alignment = Aligned16,
            vectorizable = true,
            masked_load_available = false,
            masked_store_available = false
        };
        typedef Packet1cd half;
        typedef Packet2d as_real;
    };

    template <> EIGEN_STRONG_INLINE Packet1cd pload<Packet1cd>(const std::complex<double>* from) { return Packet1cd(pload<Packet2d>((const double*)from)); }
    template <> EIGEN_STRONG_INLINE Packet1cd ploadu<Packet1cd>(const std::complex<double>* from) { return Packet1cd(ploadu<Packet2d>((const double*)from)); }
    template <> EIGEN_STRONG_INLINE void pstore<std::complex<double>>(std::complex<double>* to, const Packet1cd& from) { pstore((double*)to, from.v); }
    template <> EIGEN_STRONG_INLINE void pstoreu<std::complex<double>>(std::complex<double>* to, const Packet1cd& from) { pstoreu((double*)to, from.v); }

    template <> EIGEN_STRONG_INLINE Packet1cd pset1<Packet1cd>(const std::complex<double>& from)
    { /* here we really have to use unaligned loads :( */
        return ploadu<Packet1cd>(&from);
    }

    template <> EIGEN_DEVICE_FUNC inline Packet1cd pgather<std::complex<double>, Packet1cd>(const std::complex<double>* from, Index)
    {
        return pload<Packet1cd>(from);
    }
    template <> EIGEN_DEVICE_FUNC inline void pscatter<std::complex<double>, Packet1cd>(std::complex<double>* to, const Packet1cd& from, Index)
    {
        pstore<std::complex<double>>(to, from);
    }

    template <> EIGEN_STRONG_INLINE Packet1cd padd<Packet1cd>(const Packet1cd& a, const Packet1cd& b) { return Packet1cd(a.v + b.v); }
    template <> EIGEN_STRONG_INLINE Packet1cd psub<Packet1cd>(const Packet1cd& a, const Packet1cd& b) { return Packet1cd(a.v - b.v); }
    template <> EIGEN_STRONG_INLINE Packet1cd pnegate(const Packet1cd& a) { return Packet1cd(pnegate(Packet2d(a.v))); }
    template <> EIGEN_STRONG_INLINE Packet1cd pconj(const Packet1cd& a) { return Packet1cd(pxor(a.v, reinterpret_cast<Packet2d>(p2ul_CONJ_XOR2))); }

    template <> EIGEN_STRONG_INLINE Packet1cd pand<Packet1cd>(const Packet1cd& a, const Packet1cd& b) { return Packet1cd(pand(a.v, b.v)); }
    template <> EIGEN_STRONG_INLINE Packet1cd por<Packet1cd>(const Packet1cd& a, const Packet1cd& b) { return Packet1cd(por(a.v, b.v)); }
    template <> EIGEN_STRONG_INLINE Packet1cd pxor<Packet1cd>(const Packet1cd& a, const Packet1cd& b) { return Packet1cd(pxor(a.v, b.v)); }
    template <> EIGEN_STRONG_INLINE Packet1cd pandnot<Packet1cd>(const Packet1cd& a, const Packet1cd& b) { return Packet1cd(pandnot(a.v, b.v)); }

    template <> EIGEN_STRONG_INLINE Packet1cd ploaddup<Packet1cd>(const std::complex<double>* from) { return pset1<Packet1cd>(*from); }

    template <> EIGEN_STRONG_INLINE void prefetch<std::complex<double>>(const std::complex<double>* addr) { EIGEN_PPC_PREFETCH(addr); }

    template <> EIGEN_STRONG_INLINE std::complex<double> pfirst<Packet1cd>(const Packet1cd& a)
    {
        EIGEN_ALIGN16 std::complex<double> res[2];
        pstore<std::complex<double>>(res, a);

        return res[0];
    }

    template <> EIGEN_STRONG_INLINE Packet1cd preverse(const Packet1cd& a) { return a; }

    template <> EIGEN_STRONG_INLINE std::complex<double> predux<Packet1cd>(const Packet1cd& a) { return pfirst(a); }

    template <> EIGEN_STRONG_INLINE std::complex<double> predux_mul<Packet1cd>(const Packet1cd& a) { return pfirst(a); }

    EIGEN_MAKE_CONJ_HELPER_CPLX_REAL(Packet1cd, Packet2d)

    template <> EIGEN_STRONG_INLINE Packet1cd pdiv<Packet1cd>(const Packet1cd& a, const Packet1cd& b)
    {
        // TODO optimize it for AltiVec
        Packet1cd res = pmul(a, pconj(b));
        Packet2d s = pmul<Packet2d>(b.v, b.v);
        return Packet1cd(pdiv(res.v, padd<Packet2d>(s, vec_perm(s, s, p16uc_REVERSE64))));
    }

    EIGEN_STRONG_INLINE Packet1cd pcplxflip /*<Packet1cd>*/ (const Packet1cd& x) { return Packet1cd(preverse(Packet2d(x.v))); }

    EIGEN_STRONG_INLINE void ptranspose(PacketBlock<Packet1cd, 2>& kernel)
    {
        Packet2d tmp = vec_perm(kernel.packet[0].v, kernel.packet[1].v, p16uc_TRANSPOSE64_HI);
        kernel.packet[1].v = vec_perm(kernel.packet[0].v, kernel.packet[1].v, p16uc_TRANSPOSE64_LO);
        kernel.packet[0].v = tmp;
    }

    template <> EIGEN_STRONG_INLINE Packet1cd pcmp_eq(const Packet1cd& a, const Packet1cd& b)
    {
        // Compare real and imaginary parts of a and b to get the mask vector:
        // [re(a)==re(b), im(a)==im(b)]
        Packet2d eq = reinterpret_cast<Packet2d>(vec_cmpeq(a.v, b.v));
        // Swap real/imag elements in the mask in to get:
        // [im(a)==im(b), re(a)==re(b)]
        Packet2d eq_swapped = reinterpret_cast<Packet2d>(vec_sld(reinterpret_cast<Packet4ui>(eq), reinterpret_cast<Packet4ui>(eq), 8));
        // Return re(a)==re(b) & im(a)==im(b) by computing bitwise AND of eq and eq_swapped
        return Packet1cd(vec_and(eq, eq_swapped));
    }

    template <> EIGEN_STRONG_INLINE Packet1cd psqrt<Packet1cd>(const Packet1cd& a) { return psqrt_complex<Packet1cd>(a); }

#endif  // __VSX__
}  // end namespace internal

}  // end namespace Eigen

#endif  // EIGEN_COMPLEX32_ALTIVEC_H
